Automatic retransmission request layer interaction in a wireless network

ABSTRACT

A base station, mobile station, and/or other terminal includes physical layer (layer  1 ) protocol and link layer (layer  2 ) protocol enhancements that interact with one another to cause the link layer protocol to inhibit is ARQ operations for data blocks having missing data packets that are still pending at the physical layer. A mobile station (or base station) receives a data packet from a base station across a wireless link. The physical layer then determines, a number, N, of data packets pending with its physical layer Automatic Retransmission reQuest (ARQ) operations. The physical layer then passes the data packet and the number, N, to a link layer operating on the mobile station. The link layer then modifies its ARQ operations based upon the number, N, of data packets pending with the physical layer ARQ operations. The link layer inhibits ARQ operations for data blocks missing data packets that are still pending with the physical layer.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority pursuant to 35 U.S.C. Sec 120 toU.S. Regular application Ser. No. 09/836,488 filed Apr. 17, 2001, whichclaimed priority pursuant to 35 U.S.C. Sec 119(e) to U.S. ProvisionalApplication Ser. No. 60/197,553, filed Apr. 17, 2000, both of which arehereby incorporated by reference in their entirety.

BACKGROUND

1. Technical Field

The present invention relates generally to cellular wirelesscommunication networks; and more particularly to the servicing ofpacketized communications within such cellular wireless communicationnetworks.

2. Related Art

Wireless networks are well known. Cellular wireless networks supportwireless communication services in many populated areas of the world.While wireless networks were initially constructed to service voicecircuit-switched voice communications, they are now called upon tosupport packet-switched data communications as well.

The transmission of packetized data communications within a wirelessnetwork places different demands on networks than does the transmissionof voice communications. Voice communications require a sustainedbandwidth with minimum signal-to-noise ratio (SNR) and continuityrequirements. Data communications, on the other hand, typically arelatency tolerant but have higher total throughput requirements.Conventional circuit-switched wireless networks were designed to supportthe well-known voice communication requirements. Thus, wireless networks(as well as conventional circuit switched telephone networks) have beenadapted to service data communications, with such adaptation providingmixed results. Thus, future wired and wireless networks will likely befully packet switched.

The Internet, Intranets, and their underlying Wide Area Networks, andLocal Area Networks are all packet switched networks. In such packetswitched networks, all communications to be transmitted from a source toa destination are packetized prior to transmission and reassembled uponreceipt. These networks are capable of servicing both datacommunications and multimedia services such as Voice Over IP (VOIP)communications. Because of the requirement of interoperability betweenthe equipment of differing vendors, various interworking standards havebeen developed for packet switched networks. Most operating standards ofthis type are based upon the well-known Industry Standards Organization(ISO) seven layer Open Systems Interconnect (OSI) model. The OSI modelincludes, from lowest protocol layer to highest protocol layer, (1) thephysical layer, (2) the data link layer, (3) the network layer, (4) thetransport layer, (5) the session layer, (6) the presentation layer, and(7) the application layer. A corresponding TCP/IP reference modelincludes (1) the physical layer, (2) the network interface layer, (3)the Internet layer, (4) the transport layer, and (5) the applicationlayer. Networked devices, e.g. computer terminals, wireless networkmobile stations, etc., operating according to these standards supporterror free transfer of data communications. Thus, almost all devicessupporting data communications operate according to one or morevariations of these operating standards.

In order to ensure that packets lost in transmission are retransmitted,the operating standards sometimes employ Automatic RetransmissionreQuest (ARQ) operations. Generally speaking, ARQ operations areemployed to automatically request retransmission of data packets thathave been transmitted but not successfully received, e.g., lost datapackets, erroneous data packets, etc.

For example, in a data session established between a client computer anda web server across the Internet, the client computer requests thedownload of a file. The web server accesses the file, subdivides therequested file into a plurality of data packets, and uniquely identifieseach data packet. The web server then transmits each of the data packetsto the client computer. Upon receipt of all of the data packets, theclient computer combines the data packets in the correct order toreconstruct the file. However, the client computer may not successfullyreceive all of the data packets from the web computer due tolost/erroneous transmissions. When this occurs, the client computerautomatically sends a request to the web server to retransmit alost/erroneously received packet. ARQ operations continue until theclient computer correctly receives all data packets that make up thefile.

ARQ operations are particularly important in wireless networks, e.g.,cellular and satellite networks that networks support wireless linksbetween a base station and a serviced mobile station. Wireless links aresubject to interference, fading, and other factors that oftentimesprevent successful first time transmission of data packets. In wirelessnetworks, more than one protocol layer may support ARQ operations, e.g.,transport layer and link layer. Further, in some networks, the physicallayer (layer 1) may also support ARQ operations. During normaloperations, however, the ARQ operations of the multiple protocol layersmay interfere with one another. Such interference introduces additionaldelays in the packet data transmissions and, in some cases, may resultsin unnecessary higher-layer retransmission or may cause a transmissionto fail by inadvertently causing a higher-layer time-out event.

Thus, there exists a need in the art for cooperative operation betweenARQ operations of different protocol layers.

SUMMARY OF THE INVENTION

In order to overcome these shortcomings, among others, a base station,mobile station, and/or other terminal includes physical layer (layer 1)protocol and link layer (layer 2) protocol enhancements that interactwith one another to prevent unnecessary link layer ARQ operations. Theseenhancements cause the link layer protocol to prevent ARQ operations fordata blocks having missing data packets that are still pending at thephysical layer.

According to one embodiment of the present invention, a physical layerprotocol operating on a mobile station receives a data packet from abase station across a wireless link. The physical layer protocol thendetermines, a number, N, of data packets pending with its physical layerprotocol Automatic Retransmission reQuest (ARQ) operations. The physicallayer protocol then passes the data packet and the number, N, to a linklayer protocol operating on the mobile station. The link layer protocolthen modifies its ARQ operations based upon the number, N, of datapackets pending with the physical layer protocol ARQ operations. Inmodifying its ARQ operations, the link layer avoids initiating ARQoperations for data blocks missing data packets that are still pendingwith the physical layer.

However, the link layer may also determine that it must initiate ARQoperations. According to one embodiment of these operations, upon thereceipt of each data packet from the physical layer, the link layerdetermines its total number of missing data packets. Then, based uponthe number, N, the link layer determines that physical layer ARQoperations have failed for at least one missing data packet of acorresponding data block. The link layer then initiates ARQ operationsfor the corresponding data block.

These operations also apply when the physical layer sends a packeterasure indication to the link layer. In such case, the physical layerdetermines that its ARQ operations have failed to recover a missing datapacket and generates a packet erasure indication for the data packet. Insuch case, the physical layer also determines a number, M, of datapackets pending with its ARQ operations. The physical layer then passesthe data packet erasure indication to the link layer protocol operatingon the mobile station. The link layer protocol then modifies its ARQoperations based upon the number, M, of data packets pending with thephysical layer protocol ARQ operations.

In one particular embodiment, the link layer maintains a counter foreach data block having missing data packets. Then, when the link layerdetermines that the counter value exceeds the number, N, it initiatesARQ operations for the data block having missing data packets. The linklayer also modifies these counter values when a missing packet isreceived to account for the received data packet.

These operations may be embodied as method or steps performed by a basestation, mobile station, or another device implementing the physicallayer protocol and the link layer protocol. These operations may also beembodied in software instructions contained on a media of a basestation, mobile station, or another device implementing the physicallayer protocol and the link layer protocol. Further, these operationsmay be embodied in software operations stored on a media or transportedvia a computer network that may be executed by a base station, mobilestation, or another device implementing the physical layer protocol andthe link layer protocol.

Other features and advantages of the present invention will becomeapparent from the following detailed description of the invention madewith reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

A better understanding of the present invention can be obtained when thefollowing detailed description of the preferred embodiment is consideredin conjunction with the following drawings, in which:

FIG. 1 is a system diagram illustrating a portion of a cellular wirelessnetwork constructed according to the present invention;

FIG. 2 is a block diagram illustrating the OSI components residing upona mobile station and a base station that operate according to thepresent invention;

FIG. 3 is a block diagram illustrating the OSI components residing upona mobile station and a wired/wireless terminal that operate according tothe present invention;

FIG. 4 is a logic diagram generally illustrating operation according tothe present invention;

FIGS. 5 and 6 are logic diagrams illustrating operation according to thepresent invention by a layer 2 protocol upon receipt of a packet from alayer 1 protocol;

FIG. 7 is a logic diagram illustrating operation according to thepresent invention by a layer 2 protocol in determining whether layer 1ARQ operations have failed for particular data block(s) and in operatingaccordingly;

FIG. 8 is a logic diagram illustrating operation according to thepresent invention by a layer 2 protocol upon receipt of a data packeterasure from a layer 1 protocol;

FIG. 9 is a block diagram illustrating a base station constructedaccording to the present invention; and

FIG. 10 is a block diagram illustrating a mobile station constructedaccording to the present invention.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 is a system diagram illustrating a portion of a cellular wirelessnetwork constructed according to the present invention. The cellularwireless network includes a wireless network infrastructure 102, basestation 104, and base station 106. The cellular wireless networkoperates according to an operating standard that may have been modifiedaccording to the present invention, e.g., HSDPA, 1xEV, etc. However, theoperations of the present invention may be implemented in some caseswithout modification of existing standards. The wireless networkinfrastructure 102 couples to the Internet 114. The wireless networkinfrastructure 102 also couples to the Public Switched Telephone Network(PSTN) 110. In one embodiment of the present invention, the networkinfrastructure 102 is circuit switched, couples directly to the PSTN110, and couples to the Internet 114 via a gateway (G/W) 112. In anotherembodiment of the present invention, the network infrastructure ispacket switched, couples directly to the Internet 114, and couples tothe PSTN via an interworking function (IWF) 108.

A conventional voice terminal 120 couples to the PSTN 110. A VoIPterminal 122 and a personal computer 124 couple to the Internet 114.Mobile stations 116, 118, 126, 128, 130, 132, 134, and 136 wirelesslycouple to the wireless network via wireless links with the base stations104 and 106. As illustrated, mobile stations may include cellulartelephones 116 and 118, laptop computers 126 and 134, desktop computers128 and 136, and data terminals 130 and 132. However, the wirelessnetwork supports communications with other types of mobile stations aswell.

Each of the base stations 104 and 106 services a cell/set of sectorswithin which it supports wireless communications. Wireless links thatinclude both forward link components and reverse link components supportwireless communications between the base stations and their servicedmobile stations. These wireless links support both data communicationsand multimedia communications, such as VoIP. The teachings of thepresent invention may be applied equally to any type of packetizedcommunication.

Each of the base stations 106 and 108 and at least some of the mobilestations 116, 118, 126, 128, 130, 132, 134, and 136 support layer 1(physical layer) ARQ and layer 2 (link layer) ARQ operations. Further,according to the present invention, layer 1 ARQ operations work incooperation with layer 2 ARQ operations to avoid unnecessaryretransmission requests. Generally speaking, when layer 1 passes a datapacket or a packet erasure to layer 2, it also passes to layer 2 anindication of the number of packets pending with its ARQ operations.Layer 2 keeps track of the pending layer 1 packets and does not requestretransmission of data blocks corresponding to these pending layer 1packets. These operations will be described in particular with referenceto FIGS. 4-8.

FIG. 2 is a block diagram illustrating the OSI components residing upona mobile station and a base station that operate according to oneembodiment of the present invention. As shown, the mobile stationsupports all seven ISO protocol layers. The base station may alsosupport all seven ISO protocol layers. However, in the example of FIG.2, the base station employs only the physical layer and link layer inservicing a communication between the mobile station and a wiredterminal. In this operating scenario, the base station simply relayslayer 2 packets between the mobile station and the wired terminal.

The protocol layer operations of FIG. 2 are compliant with one of anumber of various standards, e.g., 1xEV, HSDPA, or another variousstandards. These standards will typically include both layer 1 and layer2 components. While layer 1 is typically referred to as the physicallayer, layer 2 is referred to using various terms, the particular term,e.g., Radio Link Protcol (RLP), etc., used dependent upon the standard.The teachings of the present invention may be applied to any operatingstandard in which layer 1 and layer 2 both support ARQ operations.

The teachings of the present invention may be applied to various ARQoperations. For example, some ARQ operations employ a “stop-and-wait”(SAW) methodology in which packets are recovered in order. However, someother ARQ operations doe not recover packets in order, e.g., Motorola'sdual channel SAW, 1xEV-DO's 4 channel SAW, Lucent's asynchronousIncremental Redundancy, and Nortel's NCP (Non-complete Puncture), amongothers. The teachings of the present invention apply to any of thesemethodologies.

As is illustrated in FIG. 2, layer 1 and layer 2 of both the mobilestation and the base station have been modified according to the presentinvention. In particular, layer 1 includes a L1-L2 modification whilelayer 2 includes a L2-L1 modification. As will be described further withreference to FIGS. 4-8, the L1-L2 modification causes layer 1 to reportthe number of packets that are pending with its ARQ operations with thepresentation of each valid data packet and each with erasure. The L2-L1modification prevents layer 2 from initiating ARQ operations for datablocks having missing data packets for which layer 1 ARQ operations arestill pending.

FIG. 3 is a block diagram illustrating the OSI components residing upona mobile station and a wired/wireless terminal that operate according tothe present invention. As compared to the components of FIG. 2, in FIG.3 the layer 1 and layer 2 modifications reside on the mobile station andthe wired terminal.

While FIGS. 2 and 3 show the modifications of the present inventionresiding on both communicating terminals, the layer 1 and layer 2modifications of the present invention may be implemented on a singledevice to provide benefits in the operation of the device. For datacommunications, the bulk of data transmitted is carried on the forwardlink from the base station to the mobile station. Including themodifications of the present invention upon the mobile station providesadvantages by reducing the number of unnecessary retransmissions on theforward link. These advantages may be obtained without implementing thelayer 1 and layer 2 modifications in the base station (or wiredterminal).

FIG. 4 is a logic diagram generally illustrating operation according tothe present invention. Operation commences with the initiation of atransmission that includes a wireless path between a base station and amobile station. One example of such a transmission, with particularreference to FIG. 1, occurs when mobile laptop computer 126 requests thedownload of a file from server computer 124 coupled to the Internet. Inresponse to the request, the server computer 124 initiates thetransmission of data to the laptop computer 126 via the Internet 114,the gateway 112 if required, the wireless network infrastructure 102,and the base station 104 to the laptop computer 124 (step 402).

In such transmission operation, layer 2 operating upon the servercomputer 124 segregates the file into a number of data blocks and layer1 operating upon the server computer 124 segregates each data block intoa plurality of data packets. Layer 1 (physical layer) operating upon thelaptop computer 126 receives a packet, determines that it is error free,and delivers the error-free packet to layer 2 (link layer). According tothe present invention, with the packet the physical layer of the laptopcomputer 124 also delivers the number of prior packets, N, that arepending recovery (step 404).

The link layer then receives the packet, processes the packet, andprocesses the pending packet indication, N (step 406, the details ofwhich are described with reference to FIGS. 5 and 6). In another similaroperation, the physical layer passes an erasure to the link layer alongwith a pending packet indication, M. These operations are described withreference to FIG. 8. The link layer then checks/updates the counters itmaintains for data blocks having missing packets (step 408, the detailsof which will be described with reference to FIG. 7).

Because ARQ operations may cause packets to be received out of order,the physical layer may receive the missing data packets and pass them tothe link layer out of sequence. Thus, the operations of step 408 areperformed so that the link layer will only initiate ARQ operations forparticular data blocks after the physical layer has completed its ARQoperations for the missing data packets of the data blocks. Theoperations of FIG. 4 are performed until the transmission is complete(or it fails). In such case, as determined at step 410, operation ends.

FIGS. 5 and 6 are logic diagrams illustrating operation according to thepresent invention by a layer 2 protocol upon receipt of a packet from alayer 1 protocol. When the physical layer delivers an error-free packetX to the link layer, it also includes the number, N, of physical layerpackets prior to packet X that are pending recovery at the physicallayer. When the link layer receives the physical layer packet X and theassociated information N, it checks the sequence number, S, of thereceived physical layer packet with the next expected sequence number,V(R), maintained by the link layer (step 502). If [S >V(R) ] (step 504),the received packet has a greater sequence number than the expectedphysical layer packet (new data loss is detected) and operation proceedsto step 512. If [S <=V(R)] (as determined step 504), either the receivedphysical layer packet is the expected physical layer packet or thereceived physical layer packet is a previously detected missing physicallayer packet. Thus, it is next determined whether [V(N) <=S <V(R)] (step506). If the determination is negative, i.e., S=V(R), the expectedphysical layer data packet has arrived and operation proceeds to FIG. 7(step 510). If the determination is positive, i.e., V(N) <=S, apreviously detected missing data has arrived and operation proceeds tothe operations of FIG. 6 (step 508).

When new data loss is detected at step 504, operation proceeds to step512 where it is determined whether any prior physical data packets arepending, i.e., is N=0? If other physical data blocks are also missing,i.e., N≠0, operation proceeds to step 518 where actions are taken in anattempt to recover the newly detected lost data packets. In such case, acounter Count_(data) _(—) _(pending) (C_(DP)) associated with the datablock of the received physical layer packet is set to N, i.e., C_(DP)=N, and a DELAY_TIMER associated with the missing data block is set(step 518). Note that a C_(DP) is assigned for each data block for whichmissing data packets are detected. From step 518, operation proceeds toFIG. 7.

If it is determined at step 512 that N=0, i.e., the physical layer isnot attempting to recover any other data packets, the link layer sendsNAK requests for the missing data packets/data block (step 514). Thelink layer then starts a NAK timer for the missing data packets/datablock (step 516) and operation proceeds to FIG. 7. If the NAK_TIMERexpires before the missing data is received, the link layer ARQ protocolcan either ask for the next retransmission or abort the link layer ARQfor this data block.

Referring now to FIG. 6, operations continue from step 508 of FIG. 5where it was determined that previously detected missing data hasarrived. This previous data may arrive as a result of a normaloperation, a physical layer ARQ operation, or a link layer ARQoperation. Upon receipt, the link layer determines whether the receiveddata packet is a duplicate (step 602). If the data packet is aduplicate, operation proceeds to FIG. 7 (step 604).

If the received data packet is not a duplicate (as determined at step602), the link layer stores the packet in the appropriate location in are-sequencing buffer (step 606). Then, the link layer determines whetheran associated counter for the missing data block, C_(DP), is active(step 608). If a C_(DP) counter is active for the data block, the linklayer reduces the C_(DP) counter by one and reduces the C_(DP)associated with subsequent missing data blocks by one (step 610). Fromstep 610, operation proceeds to FIG. 7. If an associated counter for themissing data block, C_(DP) is not active/is disabled (as determined atstep 608) this implies that a layer 2 NAK was previously generated forthis missing data packet. In such case, a first data block havingmissing data is considered (step 612) to determine if C_(DP) (previousmissing data block)<=N<C_(DP) (this missing data block) (step 614). Ifthe condition is satisfied for the missing data block underconsideration, the C_(DP) (this missing data block) is decremented byone and the C_(DP) of all subsequent missing data blocks are decrementedby one (step 610). From step 610, operation proceeds to FIG. 7. If thecondition is not met for the missing data block under consideration, itis determined whether the missing data block under consideration is thelast missing data block to be considered (step 616). If not, operationproceeds to step 612 wherein the next missing data block is considered.If so, operation proceeds to FIG. 7 Note that the conditional check ofstep 614 passes for one and only one missing data block during normaloperations.

FIG. 7 is a logic diagram illustrating operation according to thepresent invention by a layer 2 (link layer) protocol in determiningwhether layer 1 (physical layer) ARQ operations have failed forparticular data block(s) and in operating accordingly. The operations ofFIG. 7 are performed upon the receipt of either a packet from layer 1 ora packet erasure from layer 1. According to these operations, the linklayer considers a first data block with missing data (step 702).

The link layer then checks the updated C_(DP) of each missing data blockto decide whether a NAK request should be generated. To make thisdetermination, the link layer determines, for a missing data block underconsideration, whether the C_(DP) (this missing data block) =C_(DP)(previous missing data block) at step 704. If this condition issatisfied, then ARQ operations of the physical layer have failed forthis missing data block and a NAK request is for this data block (step706). Then, the C_(DP) and DELAY_TIMER associated with this data blockare disabled (step 708).

From step 708, and from step 704 when the condition was not satisfied,operation proceeds to step 710 where it is determined whether themissing data block under consideration. If so, operation proceeds tostep 410 of FIG. 4 (step 712). If not, operation returns to step 702where a next data block with missing data is considered.

If the DELAY_TIMER expires before any NAK is generated for the missingdata block, a NAK requesting retransmission of the data block is sent bythe link layer to the physical layer. Note that the DELAY_TIMER is usedas a safe-guard for the case where the physical layer is unable todetect an erasure due to poor signal-to-interference level. When thisoccurs, the C_(DP) and DELAY_TIMER associated with the data block aredisabled. The operations of the present invention may also be realizedby storing the delta between N (this missing data block) and N (previousmissing data block) in the C_(DP) counter (this missing data block).This approach would realize the same benefits in a slightly differentmanner.

FIG. 8 is a logic diagram illustrating operation according to thepresent invention by a layer 2 (link layer) protocol upon receipt of apacket erasure from a layer 1 (physical layer) protocol. When thephysical layer recognizes that its ARQ operations have failed for aparticular physical layer data packet, it delivers an erasure indicationto the link layer with the number of prior packets, M, pending recoveryat the physical layer (step 802). Based upon this information, the linklayer updates its information regarding missing data blocks still havedata packet recovery operations pending at the physical layer.

To accomplish this goal, the link layer considers the first data blockwith missing data to determine if C_(DP) (previous missing datablock)<=M <C_(DP) (this missing data block) (step 806). If the conditionis satisfied for the missing data block under consideration, the C_(DP)(this missing data block) is decremented by one and the C_(DP) of allsubsequent missing data blocks are decremented by one (step 808). If atstep 806, the condition is not satisfied, operation proceeds to step810. At step 810, the link layer determines whether all data blocks withmissing data have been considered. If not, operation returns to step 804where the next data block with missing data is considered. If so,operation proceeds to FIG. 7.

FIG. 9 is a block diagram illustrating a base station 902 constructedaccording to the present invention. FIG. 9 is a block diagramillustrating a base station 902 constructed according to the presentinvention that performs the operations previously described herein. Thebase station 902 supports an operating protocol, e.g., IS-95A, IS-95B,IS-2000, GSM-EDGE, and/or various 3G and 4G standards that arecompatible with the teachings of the present invention, with our withoutmodification thereto. However, in other embodiments, the base station902 supports other operating standards. The base station 902 supportsprotocol layer operations such as those described with reference to FIG.2.

The base station 902 includes a processor 904, dynamic RAM 906, staticRAM 908, Flash memory, EPROM 910 and at least one data storage device912, such as a hard drive, optical drive, tape drive, etc. Thesecomponents (which may be contained on a peripheral processing card ormodule) intercouple via a local bus 917 and couple to a peripheral bus920 (which may be a back plane) via an interface 918. Various peripheralcards couple to the peripheral bus 920. These peripheral cards include anetwork infrastructure interface card 924, which couples the basestation 902 to the wireless network infrastructure 950. Digitalprocessing cards 926, 928, and 930 couple to Radio Frequency (RF) units932, 934, and 936, respectively. Each of these digital processing cards926, 928, and 930 performs digital processing for a respective sector,e.g., sector 1, sector 2, or sector 3, serviced by the base station 902.Thus, each of the digital processing cards 926, 928, and 930 willperform some or all of processing operations described with reference toFIGS. 6 and 7. The RF units 932, 934, and 936 couple to antennas 942,944, and 946, respectively, and support wireless communication betweenthe base station 902 and mobile stations (the structure of which isshown in FIG. 9). The base station 902 may include other cards 940 aswell.

Hybrid Automatic Retransmission reQuest Instructions (HARQI) 916 arestored in storage 912. The HARQI 916 are downloaded to the processor 904and/or the DRAM 906 as HARQI 914 for execution by the processor 904.While the HARQI 916 are shown to reside within storage 912 contained inbase station 902, the HARQI 916 may be loaded onto portable media suchas magnetic media, optical media, or electronic media. Further, theHARQI 916 may be electronically transmitted from one computer to anotheracross a data communication path. These embodiments of the HARQI are allwithin the spirit and scope of the present invention.

Upon execution of the HARQI 914, the base station 902 performsoperations according to the present invention previously describedherein with reference to FIGS. 1-8. The HARQI 916 may also be partiallyexecuted by the digital processing cards 926, 928, and 930 and/or othercomponents of the base station 902. Further, the structure of the basestation 902 illustrated is only one of many varied base stationstructures that could be operated according to the teachings of thepresent invention.

FIG. 10 is a block diagram illustrating a mobile station 1002constructed according to the present invention that performs theoperations previously described herein. The mobile station 1002 supportsa CDMA operating protocol, e.g., IS-95A, IS-95B, IS-2000, and/or various3G and 4G standards that are compatible with the teachings of thepresent invention, with or without modification. However, in otherembodiments, the mobile station 1002 supports other operating standards.

The mobile station 1002 includes an RF unit 1004, a processor 1006, anda memory 1008. The RF unit 1004 couples to an antenna 1005 that may belocated internal or external to the case of the mobile station 1002. Theprocessor 1006 may be an Application Specific Integrated Circuit (ASIC)or another type of processor that is capable of operating the mobilestation 1002 according to the present invention. The memory 1008includes both static and dynamic components, e.g., DRAM, SRAM, ROM,EEPROM, etc. In some embodiments, the memory 1008 may be partially orfully contained upon an ASIC that also includes the processor 1006. Auser interface 1010 includes a display, a keyboard, a speaker, amicrophone, and a data interface, and may include other user interfacecomponents. The RF unit 1004, the processor 1006, the memory 1008, andthe user interface 1010 couple via one or more communicationbuses/links. A battery 1012 also couples to and powers the RF unit 1004,the processor 1006, the memory 1008, and the user interface 1010.

Hybrid Automatic Retransmission reQuest Instructions (HARQI) 1016 arestored in memory 1008. The HARQI 1016 are downloaded to the processor1006 as HARQI 1014 for execution by the processor 1006. The HARQI 1016may also be partially executed by the RF unit 1004 in some embodiments.The HARQI 1016 may be programmed into the mobile station 1002 at thetime of manufacture, during a service provisioning operation, such as anover-the-air service provisioning operation, or during a parameterupdating operation. Upon their execution, the HARQI 1014 cause themobile station 1002 to perform operations according to the presentinvention previously described with reference to FIGS. 1-8.

The structure of the mobile station 1002 illustrated is only an exampleof one mobile station structure. Many other varied mobile stationstructures could be operated according to the teachings of the presentinvention. Upon execution of the HARQI 1014, the mobile station 1002performs operations according to the present invention previouslydescribed herein in servicing a VOIP telephony call.

The invention disclosed herein is susceptible to various modificationsand alternative forms. Specific embodiments therefore have been shown byway of example in the drawings and detailed description. It should beunderstood, however, that the drawings and detailed description theretoare not intended to limit the invention to the particular formdisclosed, but on the contrary, the invention is to cover allmodifications, equivalents and alternatives falling within the spiritand scope of the present invention as defined by the claims.

What is claimed is:
 1. A method for operating a mobile station toreceive packetized data from a base station, the method comprising:receiving, by a physical layer (layer 1) protocol operating on themobile station, a data packet from the base station across a wirelesslink; determining, by the physical layer protocol, a number, N, of datapackets pending with its physical layer protocol AutomaticRetransmission reQuest (ARQ) operations; passing, by the physical layerprotocol, the data packet and the number, N, to a link layer (layer 2)protocol operating on the mobile station; and modifying, by the linklayer protocol, its ARQ operations based upon the number, N, of datapackets pending with the physical layer protocol ARQ operations.
 2. Themethod of claim 1, wherein: the link layer constructs the data blocksfrom data packets received from the physical layer; and the link layerdetermines its total number of missing data packets; based upon thenumber, N, the link layer determines that physical layer ARQ operationshave failed for at least one missing data packet of a corresponding datablock; and the link layer initiates ARQ operations for the correspondingdata block.
 3. The method of claim 1, wherein in modifying its ARQoperations, the link layer protocol inhibits the production of an ARQoperation for a data block having a missing data packet for whichphysical layer ARQ operations are still pending.
 4. The method of claim1, further comprising: determining, by the physical layer protocoloperating on the mobile station, a data packet erasure; determining, bythe physical layer protocol, a number, M, of data packets pending withits physical layer protocol Automatic Retransmission reQuest (ARQ)operations; passing, by the physical layer protocol, the data packeterasure to the link layer protocol operating on the mobile station alongwith the number, M; and modifying, by the link layer protocol, its ARQoperations based upon the number, M, of data packets pending with thephysical layer protocol ARQ operations.
 5. The method of claim 1,further comprising: maintaining, by the link layer, a counter for eachdata block having missing data packets; and initiating, by the linklayer when a counter for a data block having missing data packetsexceeds the number, N, ARQ operations for the data block having missingdata packets.
 6. The method of claim 5, further comprising modifying, bythe link layer, at least one counter for a data block having missingdata packets when a missing packet is received.
 7. A method foroperating a base station to receive packetized data from a mobilestation, the method comprising: receiving, by a physical layer (layer 1)protocol operating on the base station, a data packet from the mobilestation across a wireless link; determining, by the physical layerprotocol, a number, N, of data packets pending with its physical layerprotocol Automatic Retransmission reQuest (ARQ) operations; passing, bythe physical layer protocol, the data packet and the number, N, to alink layer (layer 2) protocol operating on the mobile station; andmodifying, by the link layer protocol, its ARQ operations based upon thenumber, N, of data packets pending with the physical layer protocol ARQoperations.
 8. The method of claim 7, wherein: the link layer constructsthe data blocks from data packets received from the physical layer; andthe link layer determines its total number of missing data packets;based upon the number, N, the link layer determines that physical layerARQ operations have failed for at least one missing data packet of acorresponding data block; and the link layer initiates ARQ operationsfor the corresponding data block.
 9. The method of claim 7, wherein inmodifying its ARQ operations, the link layer protocol inhibits theproduction of an ARQ operation for a data block having a missing datapacket for which physical layer ARQ operations are still pending. 10.The method of claim 7, further comprising: determining, by the physicallayer protocol operating on the base station, a data packet erasure;determining, by the physical layer protocol, a number, M, of datapackets pending with its physical layer protocol AutomaticRetransmission reQuest (ARQ) operations; passing, by the physical layerprotocol, the data packet erasure to the link layer protocol operatingon the mobile station along with the number, M; and modifying, by thelink layer protocol, its ARQ operations based upon the number, M, ofdata packets pending with the physical layer protocol ARQ operations.11. The method of claim 7, further comprising: maintaining, by the linklayer, a counter for each data block having missing data packets; andinitiating, by the link layer when a counter for a data block havingmissing data packets exceeds the number, N, ARQ operations for the datablock having missing data packets.
 12. The method of claim 11, furthercomprising modifying, by the link layer, at least one counter for a datablock having missing data packets when a missing packet is received. 13.A mobile station that operates to receive packetized data from a basestation, the mobile station comprising: an antenna; a Radio Frequencyunit coupled to the antenna; and at least one digital processor coupledto the Radio Frequency unit that executes software instructions causingthe mobile station to: receive, by a physical layer (layer 1) protocoloperating on the mobile station, a data packet from the base stationacross a wireless link; determine, by the physical layer protocol, anumber, N, of data packets pending with its physical layer protocolAutomatic Retransmission reQuest (ARQ) operations; pass, by the physicallayer protocol, the data packet and the number, N, to a link layer(layer 2) protocol operating on the mobile station; and modify, by thelink layer protocol, its ARQ operations based upon the number, N, ofdata packets pending with the physical layer protocol ARQ operations.14. The mobile station of claim 13, wherein: the link layer constructsthe data blocks from data packets received from the physical layer; andthe link layer determines its total number of missing data packets;based upon the number, N, the link layer determines that physical layerARQ operations have failed for at least one missing data packet of acorresponding data block; and the link layer initiates ARQ operationsfor the corresponding data block.
 15. The mobile station of claim 13,wherein in modifying its ARQ operations, the link layer protocolinhibits the production of an ARQ operation for a data block having amissing data packet for which physical layer ARQ operations are stillpending.
 16. The mobile station of claim 13, wherein the softwareinstructions further cause the mobile station to: determine, by thephysical layer protocol operating on the mobile station, a data packeterasure; determine, by the physical layer protocol, a number, M, of datapackets pending with its physical layer protocol AutomaticRetransmission reQuest (ARQ) operations; pass, by the physical layerprotocol, the data packet erasure to the link layer protocol operatingon the mobile station along with the number, M; and modify, by the linklayer protocol, its ARQ operations based upon the number, M, of datapackets pending with the physical layer protocol ARQ operations.
 17. Themobile station of claim 13, wherein the software instructions furthercause the mobile station to: maintain, by the link layer, a counter foreach data block having missing data packets; and initiate, by the linklayer when a counter for a data block having missing data packetsexceeds the number, N, ARQ operations for the data block having missingdata packets.
 18. The mobile station of claim 17, wherein the softwareinstructions further cause the mobile station to modify at least onecounter for a data block having missing data packets when a missingpacket is received.
 19. A base station that operates to receivepacketized data from a mobile station, the base station comprising: anantenna; a Radio Frequency unit coupled to the antenna; and at least onedigital processor coupled to the Radio Frequency unit that executessoftware instructions causing the base station to: receive, by aphysical layer (layer 1) protocol operating on the base station, a datapacket from the mobile station across a wireless link; determine, by thephysical layer protocol, a number, N, of data packets pending with itsphysical layer protocol Automatic Retransmission reQuest (ARQ)operations; pass, by the physical layer protocol, the data packet andthe number, N, to a link layer (layer 2) protocol operating on the basestation; and modify, by the link layer protocol, its ARQ operationsbased upon the number, N, of data packets pending with the physicallayer protocol ARQ operations.
 20. The base station of claim 19,wherein: the link layer constructs the data blocks from data packetsreceived from the physical layer; and the link layer determines itstotal number of missing data packets; based upon the number, N, the linklayer determines that physical layer ARQ operations have failed for atleast one missing data packet of a corresponding data block; and thelink layer initiates ARQ operations for the corresponding data block.21. The base station of claim 19, wherein in modifying its ARQoperations, the link layer protocol inhibits the production of an ARQoperation for a data block having a missing data packet for whichphysical layer ARQ operations are still pending.
 22. The base station ofclaim 19, wherein the software instructions further cause the basestation to: determine, by the physical layer protocol operating on thebase station, a data packet erasure; determine, by the physical layerprotocol, a number, M, of data packets pending with its physical layerprotocol Automatic Retransmission reQuest (ARQ) operations; pass, by thephysical layer protocol, the data packet erasure to the link layerprotocol operating on the base station along with the number, M; andmodify, by the link layer protocol, its ARQ operations based upon thenumber, M, of data packets pending with the physical layer protocol ARQoperations.
 23. The base station of claim 19, wherein the softwareinstructions further cause the base station to: maintain, by the linklayer, a counter for each data block having missing data packets; andinitiate, by the link layer when a counter for a data block havingmissing data packets exceeds the number, N, ARQ operations for the datablock having missing data packets.
 24. The base station of claim 23,wherein the software instructions further cause the base station tomodify at least one counter for a data block having missing data packetswhen a missing packet is received.
 25. A plurality of softwareinstructions stored on a media that, upon execution by a mobile station,cause the mobile station to receive packetized data from a base station,the plurality of software instructions comprising: a set of instructionsexecuted by the mobile station that cause the mobile station to receive,by a physical layer (layer 1) protocol operating on the mobile station,a data packet from the base station across a wireless link; a set ofinstructions executed by the mobile station that cause the mobilestation to determine, by the physical layer protocol, a number, N, ofdata packets pending with its physical layer protocol AutomaticRetransmission reQuest (ARQ) operation; a set of instructions executedby the mobile station that cause the mobile station to pass, by thephysical layer protocol, the data packet and the number, N, to a linklayer (layer 2) protocol operating on the mobile station; and a set ofinstructions executed by the mobile station that cause the mobilestation to modify, by the link layer protocol, its ARQ operations basedupon the number, N, of data packets pending with the physical layerprotocol ARQ operations.
 26. A plurality of software instructions storedon a media that, upon execution by a base station, cause the basestation to receive packetized data from a mobile station, the pluralityof software instructions comprising: a set of instructions executed bythe base station that cause the base station to receive, by a physicallayer (layer 1) protocol operating on the base station, a data packetfrom the mobile station across a wireless link; a set of instructionsexecuted by the base station that cause the base station to determine,by the physical layer protocol, a number, N, of data packets pendingwith its physical layer protocol Automatic Retransmission reQuest (ARQ)operation; a set of instructions executed by the base station that causethe base station to pass, by the physical layer protocol, the datapacket and the number, N, to a link layer (layer 2) protocol operatingon the mobile station; and a set of instructions executed by the basestation that cause the base station to modify, by the link layerprotocol, its ARQ operations based upon the number, N, of data packetspending with the physical layer protocol ARQ operations.